Patentable/Patents/US-8160368
US-8160368

Image feature extraction method and image compression method

PublishedApril 17, 2012
Assigneenot available in USPTO data we have
Inventorsnot available in USPTO data we have
Technical Abstract

The image feature extraction method of the present invention includes: the step of performing k2 dividing process at least once on a given image so as to convert the given image into a multi-divided image, where the k2 dividing process comprises the steps of: a) creating matrix T based on image matrix X; b) computing singular values of the matrix T; c) determining whether or not minj|σj−σj−1|>ε; d) if the result of the determination in the step c) is “No”, returning to the step c) subsequent to computing the singular values of the enlarged matrix Tα; e) if the result of the determination in the step c) is “Yes”, obtaining U which satisfies T=USVT; f) obtaining matrix T1=UTT; and g) creating image matrix X1 based on matrix T1.

Patent Claims
20 claims

Legal claims defining the scope of protection, as filed with the USPTO.

1

1. An image feature extraction method for extracting a feature of an image, comprising the step of performing k 2 (k is an arbitrary integer greater than or equal to 2) dividing process at least once on a given image so as to convert the given image into a multi-divided image, wherein the k 2 dividing process comprises the steps of: a) creating matrix T based on image matrix X; b) computing singular values σ 1 , σ 2 , . . . , σ k^2 of the matrix T, where σ 1 ≧σ 2 ≧ . . . ≧σ k^2 ; c) determining whether or not min j |σ j −σ j−1 |>ε, where ε shows a constant greater than or equal to machine epsilon; d) if the result of the determination in the step c) is “No” returning to the step c) subsequent to computing the singular values of enlarged matrix T α ; e) if the result of the determination in the step c) is “Yes”, obtaining U which satisfies T=USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), U is an orthogonal matrix and V is an orthogonal matrix; f) obtaining matrix T 1 =U T T; and g) creating image matrix X 1 based on matrix T 1 , wherein the computing the singular values of the enlarged matrix T α in the step d) comprises the steps of: creating enlarged matrix T α based on matrix T and a frame added to at least a portion of at least one side of image matrix X, the frame having a size of at least k pixels and k pixels; and computing singular values σ 1 , σ 2 , . . . , σ k^2 of the enlarged matrix T α , where σ 1 ≧σ 2 ≧ . . . ≧σ k^2 .

2

2. An image feature extraction method for extracting a feature of an image, comprising the step of performing k 2 (k is an arbitrary integer greater than or equal to 2) dividing process at least once on a given image so as to convert the given image into a multi-divided image, wherein the k 2 dividing process comprises the steps of: a) creating matrix T based on image matrix X; b) obtaining a singular value decomposition of the matrix T, T=USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), σ 1 , σ 2 , . . . , σ k^2 are singular values of T satisfying σ 1 ≧σ 2 ≧ . . . ≧σ k^2 , U is an orthogonal matrix and V is an orthogonal matrix; c) determining whether or not min j |σ j −σ j−1 |>ε, where ε shows a constant greater than or equal to machine epsilon; d) if the result of the determination in the step c) is “No”, returning to the step c) subsequent to performing singular value decomposition of enlarged matrix T α ; e) if the result of the determination in the step c) is “Yes”, obtaining matrix T 1 =U T T; and f) obtaining matrix T 1 =U T T based on matrix T 1 , wherein the performing singular value decomposition of enlarged matrix T α comprises the steps of: creating enlarged matrix T α based on matrix T and a frame added to at least a portion of at least one side of image matrix X, the frame having a size of at least k pixels and k pixels; and obtaining the singular value decomposition of the enlarged matrix T α , T α =USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), σ 1 , σ 2 , . . . , σ k^2 is a singular value of T α which satisfies σ 1 ≧σ 2 ≧ . . . ≧σ k^2 , U is an orthogonal matrix, and V is an orthogonal matrix.

3

3. An image feature extraction method according to claim 1 , wherein the image is a gray scale image or a color image.

4

4. An image feature extraction method according to claim 2 , wherein the image is a gray scale image or a color image.

5

5. An image feature extraction method according to claim 1 , wherein the singular value decompositions of the T and the T α are performed by floating point arithmetic.

6

6. An image feature extraction method according to claim 2 , wherein the singular value decompositions of the T and the T α are performed by floating point arithmetic.

7

7. An image feature extraction method according to claim 1 , wherein the singular value decompositions of the T and the T α are performed by integer arithmetic.

8

8. An image feature extraction method according to claim 2 , wherein the singular value decompositions of the T and the T α are performed by integer arithmetic.

9

9. An image feature extraction method according to claim 1 , wherein a known k 2 dividing process is used together with the k 2 dividing process, so that the given image matrix X is converted into a multi-divided image.

10

10. An image feature extraction method according to claim 2 , wherein a known k 2 dividing process is used together with the k 2 dividing process, so that the given image matrix X is converted into a multi-divided image.

11

11. An image compression method for compressing an image, comprising the steps of: performing k 2 (k is an arbitrary integer greater than or equal to 2) dividing process at least once on a given image so as to convert the given image into a multi-divided image; and performing a data compression process on the multi-divided image so as to create a compressed image, wherein the k 2 dividing process comprises the steps of: a) creating matrix T based on image matrix X; b) computing singular values σ 1 , σ 2 , . . . , σ k^2 of the matrix T, where σ 1 ≧σ 2 ≧ . . . ≧σ k^2 ; c) determining whether or not min j |σ j −σ j−1 |>ε, where ε shows a constant greater than or equal to machine epsilon; d) if the result of the determination in the step c) is “No”, returning to the step c) subsequent to computing the singular values of the enlarged matrix T α ; e) if the result of the determination in the step c) is “Yes”, obtaining U which satisfies T=USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), U is an orthogonal matrix and V is an orthogonal matrix; f) obtaining matrix T 1 =U T T; and g) creating image matrix X 1 based on matrix T 1 , wherein the computing the singular values of the enlarged matrix T α in the step d) comprises the steps of: creating enlarged matrix T α based on matrix T and a frame added to at least a portion of at least one side of image matrix X, the frame having a size of at least k pixels and k pixels; and computing singular values σ 1 , σ 2 , . . . , σ k^2 of the enlarged matrix T α , where σ 1 ≧σ 2 ≧ . . . ≧σ k^2 .

12

12. An image compression method for compressing an image, comprising the steps of: performing k 2 (k is an arbitrary integer greater than or equal to 2) dividing process at least once on a given image so as to convert the given image into a multi-divided image; and performing a data compression process on the multi-divided image so as to create a compressed image, wherein the k 2 dividing process comprises the steps of: a) creating matrix T based on image matrix X; b) obtaining a singular value decomposition of the matrix T, T=USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), σ 1 , σ 2 , . . . , σ k^2 are singular values of T satisfying σ 1 ≧σ 2 ≧ . . . ≧σ k^2 , U is an orthogonal matrix and V is an orthogonal matrix; c) determining whether or not min j |σ j −σ j−1 |>ε, where ε shows a constant greater than or equal to machine epsilon; d) if the result of the determination in the step c) is “No”, returning to the step c) subsequent to performing singular value decomposition of enlarged matrix T α ; e) if the result of the determination in the step c) is “Yes”, obtaining matrix T 1 =U T T; and f) obtaining matrix T 1 =U T T based on matrix T 1 , wherein the performing singular value decomposition of enlarged matrix T α comprises the steps of: creating enlarged matrix T α based on matrix T and a frame added to at least a portion of at least one side of image matrix X, the frame having a size of at least k pixels and k pixels; and obtaining the singular value decomposition of the enlarged matrix T α , T α =USV T , where S=diag (σ 1 , σ 2 , . . . , σ k^2 ), σ 1 , σ 2 , . . . , σ k^2 is a singular value of T α which satisfies σ 1 ≧σ 2 ≧ . . . ≧σ k^2 , U is an orthogonal matrix, and V is an orthogonal matrix.

13

13. An image compression method according to claim 11 , wherein the image is a gray scale image or a color image.

14

14. An image compression method according to claim 12 , wherein the image is a gray scale image or a color image.

15

15. An image compression method according to claim 11 , wherein the singular value decompositions of the T and the T α are performed by floating point arithmetic.

16

16. An image compression method according to claim 12 , wherein the singular value decompositions of the T and the T α are performed by floating point arithmetic.

17

17. An image compression method according to claim 11 , wherein the singular value decomposition of the T and the T α are performed by integer arithmetic.

18

18. An image compression method according to claim 12 , wherein the singular value decomposition of the T and the T α are performed by integer arithmetic.

19

19. An image compression method according to claim 11 , wherein a known k 2 dividing process is used together with the k 2 dividing process, so that the given image matrix X is converted into a multi-divided image.

20

20. An image compression method according to claim 12 , wherein a known k 2 dividing process is used together with the k 2 dividing process, so that the given image matrix X is converted into a multi-divided image.

Classification Codes (CPC)

Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.

Patent Metadata

Filing Date

February 2, 2007

Publication Date

April 17, 2012

Want to explore more patents?

Browse 5M+ US patents with plain-English claim translations and AI-generated analysis.

Citation & reuse

Analysis on this page is generated by Patentable — an AI-powered patent intelligence platform. AI-generated summaries, explanations, and analysis may be reused with attribution and a visible link back to the canonical URL below. Patent abstracts and claims are USPTO public domain.

Cite as: Patentable. “Image feature extraction method and image compression method” (US-8160368). https://patentable.app/patents/US-8160368

© 2026 Patentable. All rights reserved.

Patentable is a research and drafting-assistant tool, not a law firm, and does not provide legal advice. Documents we generate are drafts for review by a licensed patent attorney.